FM 22-5 Infantry Drill Regulations 1941-08-04
"Basic strengths of units are governed by appropriate Tables of Organization. The diagrams of organizations shown in the figures herein are based specifically on approved Tables of Organization. They must be adapted to the actual strength of the units concerned. They may be adapted to any type of unit; to changes in Tables of Organization; and to the drill space available."
Digitized by AHEC (U.S. Army Heritage Collections) http://www.carlisle.army.mil/ahec/
Changes nos. 1-2 (12, 2 p.)--inserted; dated 1942